vertical temperature gradient. At greater depths (11°C and 12°C 

 isotherms), the amplitudes were as high as 30-50 feet. Accurately 

 observed isotherm depths in all oceans show similar vertical 

 changes with distance and time. 



Temperature Inversion 



The second example (fig. 7) was recorded 90 miles south- 

 east of the first example, where the water was warmer and the 

 thermocline details changed. The deeper isotherms showed a 

 radically different pattern. The surface layer in the southern part 

 (left) was 150 feet thick, shallower than the previous sample, and 

 mixed. In the northern part (right), a weak gradient containing 

 one isotherm was above the main thermocline, and the temperature 

 inversion below the thermocline was unusual. Since the surface 

 current and surface layer were moving from north to south, it can 

 be assumed that some of the water in the thermocline was also 



SEA SURFACE 



MAIN 



THERMOCLINE -« CURRENT DIRECTION 



.18° C, 



l*f 



»19°C.,._-. 



19°C 



\j/\ ,/*/- 



Figure 7. Temperature inversions below the main thermocline (Position 2, fig 5). 



11 



